To the Editor
The coronavirus disease (COVID-19) pandemic has led to awareness of the heightened
risk for the anesthesia provider. A recent joint position statement by the American
Society of Anesthesiologists, the Anesthesia Patient Safety Foundation, the American
Academy of Anesthesiologist Assistants, and the American Association of Nurse Anesthetists
recommended as optimal practice that all anesthesia professionals utilize personal
protective equipment (PPE) appropriate for aerosol-generating procedures for all patients.
However, there remains a shortage of PPE, and some institutions still limit the use
of N95 respirators and powered air-purifying respirators (PAPRs) for confirmed COVID
cases. Because of this scarcity, physical barriers have been proposed as a means of
protecting personnel during airway instrumentation. The first “aerosol box” was designed
and shared on social media by a Taiwanese anesthesiologist, Dr Hsien-Yung Lai.
This transparent plastic cube was designed to allow the patient to lie at the head
of the operating room table, separated from the anesthesia provider by a clear barrier,
with 2circular openings at the superior end to allow the clinician’s hands to pass
through and perform airway manipulation. Canelli et al
recently demonstrated that a simulated cough resulted in contamination of the inner
surface of the box and the laryngoscopist’s gloves and gowned forearms, as opposed
to pollution of the operating room environment more than 2 m away when no barrier
With current lack of widespread point-of-care testing, there remains the risk of transmission
from asymptomatic carriers.
Moreover, during surgery, other aerosol-generating procedures might be required intraoperatively
and at emergence, including the nebulization of inhaled beta-agonist, emergent reintubation,
oropharyngeal suctioning, extubation of the endotracheal tube, and delivery of high-flow
oxygen. These same measures are also performed during monitored anesthesia care (MAC)
cases. In addition, certain types of procedures typically done under MAC, such as
upper endoscopy, can cause a high incidence of coughing.
Depending on the stability of the structure, intubation shields may be left at the
head of the operating room table for the duration of the surgical procedure as opposed
to immediately removed after successful endotracheal intubation. A small clear drape
can be used to cover the ports while allowing the anesthesia provider ready access
to the patient’s airway (Figure). At the end of the case, these physical barriers
can be easily cleaned with spray disinfectant and/or germicidal disposable wipes.
As with all novel techniques, there remains a learning curve to familiarize oneself
for use in everyday practice. Finally, in certain cases, the patient’s body habitus,
anatomical location of the surgery, or surgical positioning may preclude the use of
the intubation shield.
A clear drape covers the 2 circular openings of the intubation shield during surgery.
With a limited supply of PPE, the intubation shield or other barrier devices could
be a reasonable cost-effective strategy to help protect anesthesia professionals and
other surgical personnel, and their usage should be considered for all cases currently
being performed in the operating room.
The author thanks Collectible Grading Authority (Norcross, GA) for the donation of
the intubation shields.
Phil B. Tsai, MD, MPH
Department of Anesthesiology
Rancho Los Amigos National Rehabilitation Center